Plants need sunlight to prepare food by the process of photosynthesis. The quality, time, and intensity of sunlight affect a plant's growth. Do not put the plant under direct sunlight. Keep it them in a well-lit room which gives them enough light.
Fresh & Clean Air
Fresh and clean air is a must for healthy growing plants. If air is polluted due to any reason, be it smoke, gases or other pollutants, it will harm your plants, limiting their ability to inhale carbon dioxide for making their food by the process of photosynthesis.
Plants need room to grow and flourish. Both the roots and foliage need enough space to enjoy a good air flow and sunlight. Overcrowding of plants or not providing them enough space will restrict their growth and increase the chances of suffering from disease.